a. Field of the Invention
This invention relates to 3-amino-5-(pyridinyl)-2(1H)-pyridinones, useful as cardiotonic agents, to their preparation and to intermediates used therein.
B. Description of the Prior Art
There is no teaching in the prior art of any cardiotonically active compounds having any chemical structure comparable to or suggestive of the instantly claimed compounds.
The Lesher and Gruett British Pat. No. 1,322,318, published July 4, 1973, discloses as intermediates 1,2-dihydro-2-oxo-6-(4- or 3-pyridinyl)-nicotinonitrile, 6-(4-or 3-pyridinyl)-2(1H)-pyridinone and 6-(4- or 3-pyridinyl)-2-pyridinamine.
The Brundage and Lesher U.S. Pat. No. 3,838,156, issued Sept. 24, 1974, discloses as intermediates 1,2-dihydro-2-oxo-6-Q'''-nicotinic acids where Q'''is 4(or 3)-pyridinyl or 4(or 3)-pyridinyl having one or two lower-alkyl substituents.
The Shionogi and Co. Japanese Pat. No. 20,295/67, published Oct. 11, 1967, shows 1-(x'-amino-2'-pyridinyl)-2-pyridinones as having "analgesic and antiphlogistic activity". Specifically shown is 1-(5'-amino-2'-pyridinyl)-2-pyridinone.